I back up chrome in Windows with Google Chrome Backup, That it saves a file with
*.gcb format. Now, How could I restore it in ubuntu 11.10 ?
in other word: How could I back up and restore chrome in ubuntu?
As you can see that is not an official tool made from Google and, more important, it is only for Windows. So you can restore a backup done with it only on Windows (with the same program I think).
Use official guides to backup your works and understand softwares, not just
One possible way to do this would be to set up Google Sign in with Chrome, this will then sync your settings inbetween your windows and ubuntu computers.